ONONDAGA COUNTY. MS 



The fact of the greatest development of gypsum being south of the northern outcrop, as 

 conclusively shown at the quarries above Springport on Cajruga lake, and the constant asso- 

 ciation of gypsum with rock salt in all its known localities, are circumstances highly favorable 

 to the existence of this mineral in New- York, since its location would be to the south of its 

 salines, where no boring has yet been made ; a position which would harmonize with the con- 

 sequence which results from the depth of the ancient Onondaga valley, requiring that the 

 source of the salines should be beyond the direct influence of free percolating waters, whose 

 outlets were in the valley. 



And finally from the discovery of rock salt in Virginia, though it be true that the deposit is 

 of a different age from that of New- York, the additional fact of the concomitance of salt and 

 gypsum at that place favors the opinion advanced by Dr. Beck, that rock salt would be disco- 

 vered in Onondaga, but not in that part of the group in which the deep boring was made. 



It is to be borne in mind, that there is no intention to restrict the salt and gypsum to any 

 particular part of the group, as matter of opinion, but as matter of fact purely, which limits 

 these products through the three counties, and gives to them a defined position. 



The dip of the group, as determined by a level made near Syracuse, is within twenty-six 

 feet to the mile ; which appears to be smaller than the apparent one, and the one which the 

 appearance of higher rocks south seem to require. Should it be the true one, and there is no 

 reason to doubt its accuracy, it extends the excavation of the ancient Onondaga valley some 

 miles south, from the softness of the mass. 



The Water-lime group rises upon the Onondaga salt group, forming the base of the lime- 

 stone range, and is an important group in the county for water cement and common lime. 

 Numerous quarries for the former, and for both, exist along the whole line. The principal 

 expositions are, near Manlius square, and along the creek below Jamesville ; in the hill at 

 Split rock ; on Nine-mile creek, below Marcellus ; and at the outlet of Skaneateles lake. The 

 two drab layers exist throughout the county, and are those which are burnt for water cement. 

 This product, from the numerous useful purposes to which it can be applied, promises to 

 become an all important article of commerce. Care, however, should always be taken to 

 select stone of a good quality, and that the proper degree of heat be given to it ; and the finer 

 it is ground, the better will be the cement. South of Manlius square, is the best locality in 

 the district to see the greatest extent of surface of one of the layers of water-lime proper. 



Oriskany sandstone. This is the next rock in the county to the Water-lime group. At the 

 limestone quarry near Manlius, a few inches of it may be seen in the road above the Water- 

 lime group, and beneath the Onondaga limestone ; also at Jamesville ; and in Onondaga val- 

 ley, to the south of the village, showing, on the west side of the valley, in the side-hill, a 

 ledge of about seven feet thick. Its greatest thickness in the district is on the old Seneca 

 road between Elbridge and Skaneateles, appearing to be about thirty feet thick. Not far 

 from thence, on a parallel road, is the quarry from whence this rock was quarried for the 

 lock at Jordan ; which, though an inferior stone to some of the limestones of the county, yet 

 resists wear and weather tolerably well, as is evidenced at the lock. 



